The female vagina is naturally colonized by a variety of bacteria, yeast, and microorganisms. For example, a normal vagina generally contains more than about 104 lactobacilli per milliliter of vaginal fluid. Under normal conditions, the vagina flora provides a mildly acidic environment that helps guard against the invasion of pathogenic microbes. Unfortunately, this vaginal balance may be easily upset by a variety of external factors that ultimately lead to vaginal infection.
Bacterial vaginosis, for example, is a polymicrobial vaginal infection believed to be caused by an increase in the number of anaerobic organisms with a concomitant decrease in lactobacilli in the vagina. The decrease in the number of lactobacilli in the vagina has the dual effect of decreasing competition for nutrients and decreasing the amount of lactic acid present (i.e., increasing the pH). This allows for the multiplication of opportunistic pathogens in the vagina, whose growth is normally suppressed by the lactobacilli and the acidic pH of the vagina. Atopobium vaginae, Bacteroides spp., Gardnerella vaginalis, Mobiluncus, Megasphera, Mycoplasma hominis, Peptostreptococcus, and Prevotella are some of the species that are prevalent during a BV infection.
Symptoms of bacterial vaginosis generally include an unpleasant smell, an elevated vaginal pH greater than about 5.0, a thin homogeneous discharge, and the presence of clue cells (i.e., vaginal epithelial cells coated with small Gram-variable rods).
Current treatment regimens for bacterial infection of the vagina involve the use of various broad spectrum antibiotics, such as metronidazole. However, antibiotics are often undesirable because they may kill a broad range of the normal bacterial flora in the vagina, including the beneficial lactobacilli. This may cause secondary complications, because the lactobacilli keep various opportunistic pathogens in the vagina in check. The treatment may then necessitate a further treatment regimen, such as the ingestion of cultured dairy products to replace the lactobacilli in the body, as well as treatment by antifungal agents. A rise in the level of anaerobes due to a lack of lactobacilli could further complicate the infection. Antibiotics, when used frequently within the vagina, may cause systemic toxicity through absorption from the vagina. Moreover, the relative ease of treatment should not be misinterpreted as having no clinical implications. Pregnancy, in particular, is a time where bacterial vaginosis can cause serious problems. Bacterial vaginosis is becoming more recognized as a contributing factor in preterm delivery, and increased morbidity and mortality during birth.
Previous efforts at tests for bacterial vaginosis have been limited to detection of biomarkers associated specifically with infection. The obvious drawback of such approaches is that a bacterial vaginosis infection must already be present for the test to detect the same. Heretofore, no test exists that can provide frequent assessment of vaginal health so as promote better hygiene behaviors and possibly alter behavior to avoid bacterial vaginosis infection as well as other infections. Specifically, no test exists in which women can be provided significant reassurance when healthy and guidance for proper vaginal care when not.
As such, a need currently exists for fast, inexpensive, and easy to use tests which are capable of informing women about their vaginal health. Methods of utilizing such tests would also be beneficial.